Republicans on Capitol Hill “are so excited. People are coming up to me, telling me they’ve been with Trump since day one,” Collins explained to reporters.

“And I kind of look and say, ‘Well, OK, if you say so.’

“Donald Trump has accomplished for us something no one thought possible. … Everything is red, and we’ve got four solid years to get this right.”

After winning the GOP nomination to be Speaker for the next two years, Ryan gave yet another shout-out to Trump — the second of the day.

“This leadership team is unified. This entire House Republican Conference is unified,” said Ryan, flanked by his leadership team. “And we are so eager to get to work with our new president-elect to fix America’s pressing problems.”

Never mind when Trump called Ryan a “very weak and ineffective leader” last month, after the Speaker announced he’d no longer try to defend or campaign with him.

Or when Breitbart News, the outlet previously helmed by incoming top White House aide Steve Bannon, published stories attacking Ryan and his family. Bannon himself also once mocked Ryan on his radio show for “rubbing his social-justice Catholicism in my nose every second.”

“I’m not looking backward; I’m looking to the future,” Ryan said when asked about Bannon.

There were a few moments that suggested the GOP’s post-election honeymoon might not last.

And Trump’s plan to spend $1 trillion on infrastructure over the next decade is causing heartburn for fiscal conservatives who came to Washington on the promise of slashing the debt and shrinking the government.

Conservative Rep. Raúl Labrador (R-Idaho) called it a “new day” for Republicans and said in most cases Congress would work “in concert” with the new president-elect. But Labrador made clear that lawmakers would not shirk their constitutional duty to serve as a check on the executive branch.

“Are we going to treat this president differently because he’s a Republican, or did we really tell the truth to the American people when we said the executive branch was overreaching in some areas?” Labrador asked. “I would hold a Republican president to the same standard as a Democratic president.

“I meant it. I hope everybody else meant it as well.”

Collins pushed back against any GOP concerns about infrastructure spending, saying Trump focused throughout the campaign on the “albatross of the $20 trillion debt hanging around the necks of our children and grandchildren.”

“You’re not going to see us driving up in debt,” Collins added. “We need to get our financial house in order. … Conservatives, I think, understand that about Mr. Trump, and we have to prove them right as we move into the first 100 days.”

But now, some of those lawmakers who will be sticking around are offering an olive branch.

“He’s our president and I’m going to work with him in advancing good policies,” said centrist Rep. Charlie Dent (R-Pa.), who wrote in independent candidate Evan McMullin instead of voting for Trump.

But he added: “If [Trump] moves in a direction that concerns me, I’m going to have to serve as a check.”

Rep. Carlos Curbelo (R-Fla.) told The Hill earlier this year that he “could never look my children in the eye” and tell them he voted for Trump.

When reminded of that quote a week after the election, Curbelo said his views haven’t changed.

“A lot of the concerns I expressed over the last year-plus, I still feel that way,” Curbelo said. “I always said that I would be willing to hold the next president accountable and that I’d be willing to work with that person no matter who it was. That’s exactly how I feel today.”

The shift in Ryan’s fortunes is a role reversal from his Democratic counterpart, House Minority Leader Nancy Pelosi (Calif.).

House Democrats agreed Tuesday to delay their leadership elections until Nov. 30 instead of holding them this week.

No one has formally announced a challenge to Pelosi, but the two-week delay could theoretically give time for another lawmaker to build support.

Ryan, meanwhile, had appeared to be in hot water before Election Day with some conservatives who felt he hadn’t done enough to help Trump.

He scolded Trump on several occasions over the last year, such as when the president-elect proposed to ban Muslim immigration to the U.S. and when he argued a judge overseeing a case against Trump University was biased because of his Mexican heritage.

And beyond that, Ryan and Trump hold differing views on issues ranging from trade to immigration to entitlement program spending.

By contrast, the overwhelming majority of Democrats on Capitol Hill steadfastly backed Clinton throughout the campaign.

Yet it’s Democrats, not Republicans, who are now feuding over their path forward.

Rep. Peter King (R-N.Y.) offered one explanation for the role reversals.